Add examples/histogram (#1)

* Add examples/histogram

* Add build CI.

* Fix tests, update CMake presets.

* Fix non-constexpr function.

.github/workflows/ci.yml

@@ -0,0 +1,29 @@
+name: ci
+on: [push]
+jobs:
+  build-linux:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: init
+        run: sudo apt update -yqq && sudo apt install -yqq ninja-build g++-13 clang-15
+      - name: configure gcc
+        run: cmake -S . --preset=default -B build -DCMAKE_CXX_COMPILER=g++-13
+      - name: configure clang
+        run: cmake -S . --preset=ninja-clang -B clang -DCMAKE_CXX_COMPILER=clang++-15
+      - name: build gcc
+        run: cmake --build build --config=Release
+      - name: build clang
+        run: cmake --build clang --config=Release
+      - name: test
+        run: cd build && ctest -C Release
+  build-windows:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: configure
+        run: cmake -S . --preset=vs22 -B build
+      - name: build
+        run: cmake --build build --config=Release
+      - name: test
+        run: cd build && ctest -C Release

CMakeLists.txt

@@ -13,6 +13,7 @@ if(CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME)
 endif()
 
 option(NOIZ_BUILD_TESTS "Build noiz tests" ${is_project_root})
+option(NOIZ_BUILD_EXAMPLES "Build noiz examples" ${is_project_root})
 
 add_library(noiz-compile-options INTERFACE)
 add_library(noiz::noiz-compile-options ALIAS noiz-compile-options)
@@ -29,6 +30,10 @@ endif()
 
 add_subdirectory(noiz)
 
+if(NOIZ_BUILD_EXAMPLES)
+  add_subdirectory(examples)
+endif()
+
 if(NOIZ_BUILD_TESTS)
   enable_testing()
   add_subdirectory(tests)

CMakePresets.json

@@ -36,6 +36,7 @@
     },
     {
       "name": "ninja-asan",
+      "description": "ASan build configuration using Ninja Multi-config",
       "inherits": "ninja-ubsan",
       "binaryDir": "${sourceDir}/out/asan",
       "cacheVariables": {
@@ -45,36 +46,21 @@
     {
       "name": "ninja-tsan",
       "inherits": "ninja-ubsan",
+      "description": "TSan build configuration using Ninja Multi-config",
       "binaryDir": "${sourceDir}/out/tsan",
       "cacheVariables": {
         "CMAKE_CXX_FLAGS": "-fsanitize=thread -O1"
       }
     },
     {
-      "name": "vs19",
-      "description": "Build configuration using Visual Studio 16 (2019)",
-      "generator": "Visual Studio 16 2019",
+      "name": "vs22",
+      "description": "Build configuration using Visual Studio 17 (2022)",
+      "generator": "Visual Studio 17 2022",
       "binaryDir": "${sourceDir}/out/vs",
       "architecture": {
         "value": "x64",
         "strategy": "external"
       }
-    },
-    {
-      "name": "vs22",
-      "description": "Build configuration using Visual Studio 17 (2022)",
-      "inherits": "vs19",
-      "generator": "Visual Studio 17 2022"
-    },
-    {
-      "name": "pre-install",
-      "description": "Debug build using Ninja Multi-config and install prefix",
-      "inherits": "default",
-      "binaryDir": "${sourceDir}/out/pre",
-      "cacheVariables": {
-        "CMAKE_PREFIX_PATH": "${sourceDir}/out/install",
-        "RR_PREINSTALLED": "ON"
-      }
     }
   ],
   "buildPresets": [
@@ -92,6 +78,16 @@
       "name": "RelWithDebInfo",
       "configurePreset": "default",
       "configuration": "RelWithDebInfo"
+    },
+    {
+      "name": "UBSan-Debug",
+      "configurePreset": "ninja-ubsan",
+      "configuration": "Debug"
+    },
+    {
+      "name": "ASan-Debug",
+      "configurePreset": "ninja-asan",
+      "configuration": "Debug"
     }
   ],
   "testPresets": [
@@ -109,6 +105,16 @@
       "name": "RelWithDebInfo",
       "configurePreset": "default",
       "configuration": "RelWithDebInfo"
+    },
+    {
+      "name": "UBSan Debug",
+      "configurePreset": "ninja-ubsan",
+      "configuration": "Debug"
+    },
+    {
+      "name": "ASan Debug",
+      "configurePreset": "ninja-asan",
+      "configuration": "Debug"
     }
   ]
 }

examples/CMakeLists.txt

@@ -0,0 +1 @@
+add_subdirectory(histogram)

examples/histogram/CMakeLists.txt

@@ -0,0 +1,12 @@
+project(noiz-histogram)
+
+add_executable(${PROJECT_NAME})
+
+target_link_libraries(${PROJECT_NAME} PRIVATE
+  noiz::noiz-lib
+  noiz::noiz-compile-options
+)
+
+target_sources(${PROJECT_NAME} PRIVATE
+  histogram.cpp
+)

examples/histogram/histogram.cpp

@@ -0,0 +1,126 @@
+#include <noiz/noise2.hpp>
+#include <charconv>
+#include <filesystem>
+#include <format>
+#include <iostream>
+#include <vector>
+
+namespace {
+template <typename Type>
+concept NumberT = std::integral<Type> || std::floating_point<Type>;
+
+template <NumberT Type>
+auto parse_as(Type& out, std::string_view const value) -> bool {
+	if (value.empty()) { return false; }
+
+	auto const* end = value.data() + value.size();
+	auto const [ptr, ec] = std::from_chars(value.data(), end, out);
+
+	return ec == std::errc{} && ptr == end;
+}
+
+struct Args {
+	std::span<char const* const> args{};
+
+	[[nodiscard]] constexpr auto next() -> std::string_view {
+		if (args.empty()) { return {}; }
+		auto const* ret = args.front();
+		args = args.subspan(1);
+		return ret;
+	}
+
+	template <NumberT Type>
+	auto next_as(Type& out, std::string_view const key) -> bool {
+		auto value = next();
+		if (value.empty()) { return true; }
+
+		if (!parse_as(out, value)) {
+			std::cerr << std::format("invalid argument: '{}' for '{}'\n", value, key);
+			return false;
+		}
+
+		return true;
+	}
+};
+
+struct Config {
+	noiz::Seed seed{noiz::detail::Generator::make_random_seed()};
+	noiz::GridExtent2 grid_extent{50, 1}; // NOLINT
+	int count{100};						  // NOLINT
+	float step{0.1f};					  // NOLINT
+
+	// syntax: [count] [step]
+	auto parse_args(Args args) -> bool {
+		if (!args.next_as(count, "count")) { return false; }
+		if (!args.next_as(step, "step")) { return false; }
+		if (!args.args.empty()) {
+			std::cerr << std::format("unrecognized argument: '{}'\n", args.next());
+			return false;
+		}
+		return true;
+	}
+};
+
+// contains logic to store data points and draw them
+class Histogram {
+  public:
+	explicit Histogram(std::size_t const levels = 10) : rows(levels) {}
+
+	auto add(float const value) -> Histogram& {
+		// compute height relative to number of rows/levels
+		auto const height = static_cast<std::size_t>((value + 1.0f) * 0.5f * static_cast<float>(rows.size()));
+		// add a new column
+		for (std::size_t index = 0; index < rows.size(); ++index) {
+			// set output "pixel" value (0 or 1)
+			auto const ch = index > height ? symbol : background;
+			// append to each row
+			rows.at(index) += ch;
+		}
+		return *this;
+	}
+
+	[[nodiscard]] auto build() const -> std::string {
+		auto ret = std::string{};
+		for (auto const& row : rows) {
+			ret += row;
+			ret += '\n';
+		}
+		return ret;
+	}
+
+	char symbol{'x'};
+	char background{'-'};
+
+  private:
+	std::vector<std::string> rows{};
+};
+} // namespace
+
+auto main(int argc, char** argv) -> int {
+	auto config = Config{};
+	auto noise = noiz::Noise2f{noiz::Seed{config.seed}, config.grid_extent};
+
+	// skip exe name (argv[0])
+	auto const args = Args{std::span{argv, static_cast<std::size_t>(argc)}.subspan(1)};
+
+	// handle --help
+	if (!args.args.empty() && args.args.front() == std::string_view{"--help"}) {
+		std::cout << std::format("Usage: {} [count(=100)] [step(=0.1)]\n", std::filesystem::path{*argv}.stem().string());
+		return EXIT_SUCCESS;
+	}
+
+	// parse args, if any
+	if (!config.parse_args(args)) { return EXIT_FAILURE; }
+
+	// build histogram
+	auto histogram = Histogram{};
+	for (int i = 0; i < config.count; ++i) {
+		// build point on line (y = 0)
+		auto const point = noiz::Vec2f{.x = static_cast<float>(i) * config.step};
+		// add noise at point
+		histogram.add(noise.at(point));
+	}
+
+	// output histogram
+	std::cout << histogram.build();
+}

noiz/include/noiz/vec2.hpp

@@ -30,7 +30,7 @@ struct Vec2 {
 		return ret;
 	}
 
-	[[nodiscard]] constexpr auto is_normalized() const -> bool { return std::abs(sqr_magnitude() - Type(1)) < epsilon_v; }
+	[[nodiscard]] auto is_normalized() const -> bool { return std::abs(sqr_magnitude() - Type(1)) < epsilon_v; }
 
 	[[nodiscard]] auto modulo(Vec2<Type> const extent) const -> Vec2<Type> {
 		assert(extent.x > Type(0) && extent.y > Type(0));

tests/tests/CMakeLists.txt

@@ -5,4 +5,4 @@ file(GLOB SOURCES CONFIGURE_DEPENDS "*.cpp")
 target_sources(${PROJECT_NAME} PRIVATE ${SOURCES})
 target_link_libraries(${PROJECT_NAME} PRIVATE noiz-test)
 
-add_test(NAME noiz-test-${NAME} COMMAND noiz-test-${NAME})
+add_test(NAME ${PROJECT_NAME} COMMAND ${PROJECT_NAME})

tests/tests/test_vec2.cpp

@@ -11,8 +11,6 @@ static_assert(noiz::Vec2f{4.0f, 9.0f} / noiz::Vec2f{2.0f, 3.0f} == noiz::Vec2f{2
 static_assert(noiz::dot(noiz::Vec2f{2.0f, 3.0f}, noiz::Vec2f{4.0f, 5.0f}) == 23.0f); // NOLINT
 static_assert(noiz::Vec2f{2.0f, 3.0f}.sqr_magnitude() == 13.0f);					 // NOLINT
 
-static_assert(noiz::Vec2f{1.0f, 0.0f}.is_normalized());
-
 ADD_TEST(vec2_magnitude) {
 	auto const vec = noiz::Vec2f{3.0f, 4.0f}; // NOLINT
 	EXPECT(vec.magnitude() == 5.0f);		  // NOLINT